The subject invention relates to an improved brake lining assembly. More specifically, the invention relates to an improved attachment for a friction pad.
As known, a brake lining assembly typically includes a friction pad that engages a brake disc for stopping a vehicle. The assembly is actuated by a piston, which is secured to a caliper. When the assembly is actuated, the friction pad contacts the brake disc, which rotates with a vehicle wheel. The friction pad is secured to a backing plate that contacts the piston.
In some friction pads, a wire screen has been welded to the backing plate, and is disposed between the backing plate and the friction pad. The wire screen is much like window screen material and is mostly open space. Thus, the screen is flexible. During assembly, the backing plate, with the screen, is inserted into a mold tool and the friction pad is molded onto the screen securing the friction pad to the backing plate. Because the screen is flexible it does not provide structural support to the pad. Therefore, the screen does not significantly enhance the working life of the friction pad, but merely functions as an attachment.
As known, the contact between the friction pad and the brake disc slowly grinds down the friction pad until the pad needs to be replaced. In addition to wearing down, the friction pad tends to crack and chip when stresses caused while stopping the vehicle are absorbed by the friction pad. Even though the friction pad may have a substantial working life left, cracks and chips may reduce the pad""s overall effectiveness resulting in required replacement. The mesh screen does not provide any structural support to the friction pad, and since it is flexible it does not absorb the forces introduced to the friction pad while braking.
Therefore, a need exists for an improved attachment for the friction pad that will absorb stresses upon the friction pad, enhancing the durability and working life of the friction pad.
A brake lining assembly of a vehicle braking system includes a backing plate and a friction pad overlying the backing plate. An engagement panel is disposed between the backing plate and the friction pad for securing the friction pad to the backing plate. The engagement panel includes a plurality of engagement apertures disposed therein with the surface area of the panel being greater than the space defined by the engagement apertures. The panel forms a rigid frame for the friction pad for providing structural support to the friction pad.
The engagement apertures form opposing acute and obtuse patterns of rows spaced on opposed sides of a centerline of the panel. The pattern is generally symmetrical and extends in opposed directions about the centerline spreading any forces on the panel to opposed sides of the centerline. This tends to cancel the forces introduced to the friction pad during braking.
In addition to securing the friction pad to the backing plate, the engagement panel provides structural support to the friction pad. The rigid engagement panel stiffens the friction pad and absorbs stresses introduces to the friction pad while the friction pad is in contact with a brake disc. The engagement panel reduces the potential for cracking of the friction pad thereby improving the durability and working life of the friction pad.